Method and apparatus for distilling liquids



1,616079 Feb. 1,1927. W'EDOWNS METHOD AND APPARATUS FOR DISTILLING LIQUIDS Filed Dec. 4, 1921 {1214 TIN 6 SURFACE 7 m/vs/vroe wazmm FZZou/ns A TTORA/EVS A Patented Feb. 1, 1927.

UNITED STATES PATENT oFFice;

WILLIAM IE. DOWNS, OF CHATHAM, NEW JERSEY; MARY GARDNER DOWNS ADMIN- ISTRATRIX OF SAID WILLIAM F. DOWNS, DECEASED.

METHOD AND APPARATUS FOR DISTILLING LIQUIDS.

Application filed December 24, 1921, Serial No. 524,566.

This invention relates to the distillation of liquids, and more particularly to such mixtures of liquids of different boiling points as crude petroleum, which is to be separated with or without the breaking down or transformation of portions of the higher boiling point constituents. l/Vhen petroleum is treated by means of my invention I am able to more rapidly and more thoroughly drive out the gasoline and to.crack or break down the higher boiling constituents to increase the yield of gasoline while controlling theing co umn of liquid of comparatively small cross sectional area, which is immediatelythereafter spread out in a comparatively thin film or layer above the normal surface of the body of the liquid, so that the lighter constituents or products of the heating action may readily escape.

As a further important feature I provide .neans for automatically maintaining the desired cyclic flow and distribution, irrespective of variations in the level of the liquid in the still, and accomplish this by means of a float maintaining the upper end of the upflow current in predetermined relationship to the main liquid level. Vapors formed in the liquid do not have to force their way upwardly through viscous and possibly cooler liquid, but are immediately carried directly to the surface in a current of the liquid so that they may freely escape without opportunity for condensation or retention in the liquid after leaving the wall or surface to which the heat is applied.

To facilitate the free escape of the vapors and maintain substantially the same spread ing action irrespective of variations in the liquid level in the still, there is provided an approximately horizontal or laterally. extending table or apron over which the liquid flows, and this is support-ed by a float so that its elevation in respect to the level of the liquid is maintained substantially constant.

In the accompanying drawing I have illustrated merely one of various possible em-' bodiments of my invention, the drawing showing a central vertical section through a still.

tionally as a chamber 10' having a. vapor outlet 11 at the upper end thereof. The still may be heated in any suitable manner, as for instance by the direct application of heating flame to the bottom or exterior thereof, or by means of a steam jacket or other source of heat. To increase the area of heating surface there is preferably employed one or more approximately vertical tubes or passage. As shown, there is one such tube 12 centrally located in respect to-the still and open at'the bottom to receive the heating means which may be an electric heating The still is illustrated somewhat conven-:,.

coil or the superheated steam or flame. The

tube is shown as closed at the upper end,

which preferably is disposed not materially below the normal liquid level in the still.

Juxtaposed to one of the walls of the still I provide means for controlling and directing convection currents in the liquid. Although this may be positioned adjacent to the outer wall, it is illustrated in the form of an annular partition or tube 13 encircling the inner wall 12, and spaced therefrom to form an annular substantially vertical liquid passage 14 which is open at the upper and lower ends. For directing the liquid to this passage there is provided a dome or inverted cup member 15 at the lower end of the tube. This serves as a collector and extends laterally a short distance above the bottom of the still. Preferably the walls incline upwardly toward the lower end of the wall 13 so that vapor and heated liquid beneath the collector are guided to the tube. The collector may have leg or lug portions 16 resting upon and supported by the bottom of the still.

In order to insure uniform operation with different levels of liquid in the still, means are provided --for holding the upper end of the tube and-the liquid level at predetermined relative elevations. As shown, the tube 13 is formed of a plurality of telescoping sections, and the *upper section 17 is supported by an annular float 18. The connection between the upper end of the tube and float reduce the effective across the same highly heated, even though the float is in the form of an approximately horizontal or" laterally extending wallor apron 19 which preferably inclines downwardly from the tube to the upper outer surface of the float. The float is preferably in the form of a metal tube hermetically sealed to form an air chamber therein. Because of this air-chamber ithas the desired buoyancy but the wall 19 and the upper section ofthe telescoping tube which are connected to the buoyancy and keep the upper slde of thefloat but slightly above the liquid level. The upper surface of this apron may have a smooth downwardly curved surface, or it may provide cascades or ripples in the sheet of liquid flowing to break it up and further facilitate the liberation of vapor from the liquid. To prevent the accumulation of vapor in the annular-chamber between the upper section 17 of the tube and the float and beneath the wall 19, the latter may have passages or tubes 20 extending In operation the still is filled to the desired level with liquid and heat is applied to the bottom of the still, and also preferably to the wall of the tube 12. The liquid which is in contact with the bottom becomes heated, and therefore tends to rise, and in doing so, is guided by the collector 15 to the vertical passage 14. Its upward movement is along the heated wall 12, and the formation of vapor in the liquid, as well as the lighter specific gravity of the liquid causes a rapid upflow in this annular passage. At the upper end of the passage liquid flows out radially over the wall or apron 19 in a comparatively thin sheet or film, and the vapor freely escapes to the upper part of the still,

and maybe conducted away through the outlet 11. It will be noted that the portion of the liquid which is most highly heated is directed to the upper surface of the body of liquid. Thus the portion of the liquid at the higher temperature and containing the most vapor will be brought to the point where the vapor may most easily escape. There no condensation of the vapor by brin ag it in contact with cooler liquid, and the iscosity of the liquid, even though comparatively high, does not prevent the free rise of the vapor to the surface and the-free escape thereof. The annular passage 14 is comparatively narrow in cross section, so that the portion within the passage may be the heat conductivity of the liquid be comparatively low.

In the heating of hydrocarbon oils the temperature may be regulated or controlled to give the desired cracking or deformation effect on the unsaturated compounds or those of higher carbon content to produce compounds of lower carbon content in the range commonly known as gasoline, and these cracked products are immediately conducted therethrough.

togthe surface and permitted to escape so that by means of my invention I am able to increase the yield of gasoline from hydrocarbon oils Without the use of high pressure,

and. by'readily controlled heating action."

The bottom of the still and the inner wall of the tube 12 may be separately heated by different means, so that the cracking effect may take place primarily in the tube, and this temperature oontrolled within close limits.

As the liquid level in the still lowers by the distillation action, the float follows the liquid level and maintains the upper end of the tube 13, the upper end of the passage 14, and the horizontal apron 19 at substantially constant relationship to theliquid level.

l/Vith my invention, acceleration of the vaporization or distillation is accomplished by reason of the fact that it is not necessary to heat the entire mass of the liquid to as high a temperature for the beginning'of the distillation action as the liquid in the rising column between the walls 12 and 13 may be a at a'considerably higher temperature than that of the main body of the liquid. N0 liquid vaporized at the higher temperature heating surface is condensed by coming into contact with the lower temperature liquid in the main body of the stil .Therefore the maximum proportion of the heat used is expended in the formation of vaporized products. The entire mass of liquid in the still is more quickly brought to the desired high temperature, due to the action of the convection currents and the fact that the heat is more quickly brought to all portions of the mass of liquid in this Way than could be done by direct conduction. In some cases where'it may be desired to separate two liquids of. different boiling points, the main body of the liquid may be maintained slightly below the boiling point of the lighter liquid and only the portion of the liquid beneath the collector and within the vertical passage maintained at a sufficiently high temperature to drive off the more volatile constituents in the liquid mixture.

The pressure maintained in the still may be above or below that of the atmosphere and may vary with liquid treated and results to be secured. It may be as high as that now used in connection with some cracking processes for producing gasoline and for the same purpose. Anhydrous aluminum chloride may be used in the stilland a reflux condenser may be used at the outlet, as in the McAfee process of gasoline production.

In the drawing the vertical annular passage 14 is shown as increasing in cross section toward the upper end. This is desirable to a limited extent, but it is to be understood that such increase'in area is very much exaggerated in the drawing, due to the showing of the walls of the tube of a thickness appropriate for a larger still and a longer,

passage open at its upper and lower ends,

said wall being adapted for the application of heat thereto to induce a circulation of liquid upwardly through said passage, and means for maintaining the upper end of said passage and the liquid level in said chamber at approximately predetermined relative elevations.

2. A vaporization apparatus including a chamber having a partition comparatively close to one wall thereof to form a liquid passage open at its upper and lower ends,

said wall being adapted for the application of heat thereto to induce a. circulation of liquid upwardly through said passage, and means for varying the position of the upper end of said partition whereby it is automatically kept in predetermined relationship to the level of the liquid in said chamber.

3, A vaporization apparatus including a chamber having a partition comparatively close to onewall thereof to form a liquid passage open at its upper and lower ends, said wall being adapted for the application of heat thereto to induce a circulation of liquid upwardly through said passage, and means for automatically raising or lowering the upper end of said partition to maintain a substantially constant elevation in respect to the liquid level in the chamber. 4. A vaporization apparatus including a chamber having a partition comparatively close" to one wall thereof to form a liquid passage open at its upper and lower ends, said wall being adapted for the application of heat thereto to induce a circulation of liquid upwardly through said passage, and'a float vertically movable in said chamber for maintaining the upper end of said passage in predetermined relationship to the liquid level in the chamber.

5. A vaporization apparatus including a chamber having a partition comparatively close to one wall thereof to form a liquid passage open at its upper and lower ends, said wall being adapted for-the application of heat thereto to induce a circulation of liquid upwardly through said passage, a wall estending'laterally from the upper end of said passage and across which the liquid;v

may flowin a comparatively thin stream from said passage to the main body of the liquid, means for maintaining the liquid level in said chamber and the elevation of said last mentioned Wall substantially constant in respect to each other..

6.-A vaporization apparatus including a liquid chamber having an outer wall and an inner cylindrical wall, said latter wall adapted to be heated from the inner surface, a tube within the li'quid chamber concentric .with said cylirgdrical wall but spaced therefrom to form an annular vertical passage and an annular float at the upper end of said tube presenting a wall defining the upper end of said passage.-

7; A vaporization apparatus including a 1 liquid chamber having a cylindrical wall adapted to be internally heated, a tube within the liquid chamber concentric with said cylindrical wall but spaced therefrom to form an annular vertical liquid passage, said tube including a plurality of telescoping sections and a float for supporting the upper section, and for increasingor decreasing the length of said tube upon variation in the liquid level in said chamber.

8. A vaporization apparatus including'a liquid chamber having a cylindrical wall adapted to be internally heated, a tube with-- vin the'liquid chamber concentric with said cylindrical Wall but spaced therefrom to form an annular vertical liquid passage, an annular float presenting an annular approximately horizontal wall connected to. the upper end ofisaid tube, and across which sa e.

The method of separating lower boiling point constituents from a liquid mixture, consisting in heating the mixture to the boiling point of the lower boiled constituents, conducting a current of the liquid and resulting vapor upwardly to the surface of the liquid, distributing the upflowing current substantially horizontally above the liquid level to facilitate the escape of the vapor portion, and automati cally maintaining the liquid level and the point of lateral distribution at predetermined relative elevations. i

10. The distillation method which'consists in heating a body of liquid, conducting a current of the heated liquid upwardly to a point above the level of the liquid, de-

paratively thin film to permit the escape of the liquid 'may flow from said annular pasvapor therefrom and the return of the unvaporized portion to the body of the liquid, and automatically varying the point of lateral delivery in accordance with variations in the level of the body of the liquid.

11. A still having a side wall, a float and a wall depending therefrom and disa posed ad acent to said side wall of the still to form therewith a vertical passage forconvection currents which may flow over the-float to rejoin the main body of liquid in the still. I

12. A still having a float and a tube depending therefrom open at both ends and formed of telescoping sections, and a dome shfiped collector at the lower end of said tu e 13. A still adapted to receive a body'of liquid to be heated, a tube therein open at both ends formed of telescoping sections, a dome shaped collector secured to the lower section, and a float secured to and supporting the upper section. Y

14. An apparatus for controlling convection currents in a body of liquid to be heated, including a substantially vertical tube open at both ends, a dome shaped collector at the lower end thereof, an annular 20 float, and a substantially horizontal wall connecting the upper end of the tube and I the upper surface of the float and across which the liquid may flow from the upper end of the tube to-rejoin the main body of 25 

